Selector switch for radio condensers or the like



K. W. JARVIS Dec. 17, 1940.

SELECTOR SWITCH FOR RADIO CONDENSERS OR THE LIKE 2 Sheets-Sheet 1 Filed May 9, 1938 K. w. JARVIS 2,225,222

SELECTOR SWITCH FOR RADIO CONDENSERS QR THE LIKE I Dec 17, 1940.

2 Sheets-Shet 2 Filed May 9, 1958 Patented Dec. 17, 1940 UNITED STATES SELECTOR SWITCH FOR RADIO CON- DENSERS OR THE LIKE Kenneth W. Jarvis, Winnetka, Ill., assignor to Seeburg Radio Corporation, Chicago, Ill., a corporation of Illinois Application May 9, 1938, Serial No. 206,863

2 Claims.

An object of my invention is to provide a selector switch of simple durable and inexpensive construction particularly adapted for automatic tunersin connection with radio 'condensers or the like.

Still a further object is to provide a condenser or other device having a movable member, such as a shaft, with means to cause the shaft to rotate and to stop in any desired predetermined position, the energization of the motor and the stoppage of the shaft being effected automatically by depression' of a selected control button or the like. More particularly it is my object to provide a motor operated control device and a manual means to initiate operation of the motor and stop it at diiferent desired positions including a series of notched disks on the shaft having contacts operable to energize a reversing motor to rotate in one direction or the other depending on which contact of any disk is placed in the circuit by a depressible button or the like, the button being connected with a combined contact element and positioning element which initially closes the circuit of the motor and when the motor has rotated the shaft to a predetermined position effects opening of the circuit after which further manual depression of the button effects accurate positioning of the disk because of coaction of the positioning element with a V-shaped notch in the disk.

A further object is to provide disks which may be. frictionally mounted on the shaft so that each disk can'be readily reset for a different station by the simple expedient of pushing the button fora given disk to cause it to rotate to a position and while the button is located in the positioning notch, the condenser can thereafter be manually adjusted to the new station desired for that particular button after which operation of the button will automatically cause the condenser to assume its new predetermined position.

Still a further object is to provide a selector switch of the character disclosed which can be used for any movable device operated by a reversible motor, control of the motor and stoppage of the device at predetermined positions being automatically effected by depression of different selected buttons or control keys or the like.

With these and other objects in view my selector consists in the construction, arrangement and combination of the various parts thereof, whereby the objects contemplated-are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawings. Although the invention is susceptible 55 of a variety of. embodiments, it is unnecessary to fully describe and illustrate more than one in order to give a full understanding of the invention both from its structural and functional standpoints. Accordingly, I have illustrated a preferred and desirable embodiment of the invention in the accompanying drawings, in which:

Figure 1 is a perspective view of a radio cabinet with my motor operated selector for radio condensers and the like mounted therein.

Figure 2 is a plan view of the selector mechaism as applied to a radio condenser.

Figure 3 is an electro diagrammatic view of the motor operated selector.

Figure 4 is a sectional view on the line 44 of Figure 2 showing the selector being operated for rotating the condenser shaft clockwise.

Figure 5 is a similar view of a portion of Figure 4 showing the condenser shaft being rotated Figure 8 is an enlarged sectional view on the line 88 of Figure 2.

- On the accompanying drawings I have used the reference character C to indicate generally a radio cabinet. Within the cabinet C a shelf II! is provided for supporting various radio apparatus which forms no part of my present invention although my invention does pertain to the condenser I2 thereof which accordingly is illustrated on the drawings. The condenser I2 is provided with any type of manual operating means such as a pulley I3 on the condenser shaft I 4 and a knob I5 projecting through the upper panel I6 of the radio cabinet C for rotating the condenser shaft I4 manually. For this purpose the control knob I5 rotates a pulley I! which in turn is belted by a belt I8 to the pulley I3.

The condenser shaft I4 has a pair of extensions Ma and I 4b. Coupling devices I9 and Illa are provided for operatively connecting the shafts I4, Ma and Nb together. The shaft I4b is adapted to be rotated by a reversible motor M, a gear train 20 being provided to cut down the speed of rotation;

It will be obvious that rotation of the motor 20 in, one direction will increase the capacity of the condenser I2 while rotation thereof in the opposite direction will decrease its capacity. For automatically energizing the motor for rotation in the proper direction and stopping the con denser shaft 4 in any predetermined position I provide on the shaft [4a a plurality of disk elements D. Each disk element comprises a pair of contact plates 2| and 22. The shapes of these plates are perhaps best shown in Figure 3. They are rigidly connected together by connector elements 23 of insulating material and rivets 24. The connector elements 23 are provided with V shaped positioning notches 25 and the ends of the contact plates 2| and 22 terminate short of these notches as shown in Figures 4, 5, 6 and '7.

The contact plates 2| are provided with central openings 26 in which are received spacers 21. The spacers 21 are threaded on the shaft Ma and have interposed between their ends cupped spring friction disks 28. The entire assembly of disks D, sleeves 21 and disks 28 are clamped on the shaft |4a by lock nuts 29. This makes the elements Ma, 21 and 28 rigidly connected together and the disks D frictionally mounted relative to the shaft 14a due to the spring disks 28 engaging the central or hub portions of the contact plates 2| on opposite sides thereof as shown in Figure 8. The purpose of this frictional mounting will hereinafter be disclosed.

The contact elements 2| are all connected together electrically as by being grounded on the shaft Ida. The contact plates 22 are all electrically connected together as by pigtail connections 30. The left hand contact plate 22 is connected by a pigtail 3| to the motor M.

I have shown a framework consisting of end plates 32 and an angle shaped cross bar 33. Mounted on the cross bar 33 but insulated therefrom are a plurality of positioning blades 34. Each blade 34 normally assumes the dotted position shown in Figure 4 and is. controlled by a manually operable member such as a button 35. The button 35 has a link 36 connected with the positioning blade 34 and slidably mounted in an escutcheon plate 31 on the top of the panel l6. Each positioning blade 34 serves as a contact to cooperate with the contact plates 2| or 22 as r shown in Figures 4 and respectively, there being provided a terminal end 38 for this purpose. The terminal end is adapted to coact with the V- shaped notch 25 as shown in Figures 6 and '7. The motor M as shown in Figure 3 is of the reversing type having a clockwise coil CW and a counter-clockwise coil CCW. The pigtail 3| connects with the counter-clockwise coil while the shaft |4a through grounded connections is connected with the clockwise coil. A. transformer T may be provided for supplying low voltage current to both coils of the motor M and to the positioning blades 34.

Practical operation In the operation of my motor operated selector, assuming the notches 25 to be set at different predetermined positions according to the scale 39 of kilocycles or meters on the panel I6, the buttons 35 can be labeled for the different stations as shown in Figure 2. When it is desired to tune in a station by one of the buttons, the button is depressed as for instance to the position shown in Figure l. This will engage the contact blade 34 with the contact plate 2| for causing clockwise rotation of the condenser shaft I4. If it so happens that the previous setting of the condenser causes the notch 25 to be in the position shown in Figure 5, then contact will be made with the contact plate 22 to cause counterclockwise rotation. Thus the condenser I4 is always restricted to rotation within its limit of a half revolution.

Assuming that operation has been effected as in Figure 5, the disk D will rotate counter-clockwise to the position shown in Figure 6 whereupon the trailing end of the contact plate 22 disengages the positioning end 38 of the blade 34 thus breaking the circuit of the motor. The motor will almost immediately stop rotating and the end 38 of the plate 34 will enter the positioning notch 25 and engage the side thereof. Due to the inclination of the side and the fact that the operators finger will still be on the button 35, the positioning end 38 will cause further slight counter-clockwise rotation of the disk D to the position of Figure 7 where the disk has been accurately positioned by the wedge action of the positioning end 38 of the blade 34 in the notch 25. The operator, as soon as he feels the positioning end drop in the notch, releases the button at which time the disk will have been properly positioned.

When it is desirable to change the setting of any particular disk D, it is merely necessary to operate it to the position shown in Figure 7 by depressing its button 35 and then while holding the button manually depressed, he readjusts the condenser l2 by manipulation of the knob l5 to whatever setting he desires on the scale 39 and then thereafter releases the button. Any subsequent depression of the button will result in the motor M automatically rotating the condenser to the newly predetermined position if it happens to be in any other position.

The pigtail connections 30 permit extreme adjustments of the disks D without the pigtails interfering with such adjustments and without the necessity of providing brushes or the like inasmuch as the shaft |4a never rotates more than one-half revolution.

My apparatus is very simple, both from the standpoint of construction and from the standpoint of electrical wiring. Also the readjustment of the various selector elements is quickly effected without having to perform any complicated operations. Changes however can be made in the construction and arrangement of the parts of my selector without departing from the real spirit and purpose of my invention. It is therefore my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents, which may be reasonably included within their scope.

I claim as my invention:

1. A control device for radio receiving apparatus and the like, including a control shaft, a selector control mechanism connected with said shaft, said mechanism including a rotatable commutator device comprising a substantially semicircular segment with an extended central portion for encircling said shaft, an arcuate segment insulatedly mounted on said semi-circular segment, and forming with said semi-circular segment a circular disc, and insulating members extending from said semi-circular segment to said arcuate segment adjacent the periphery of said circular disc, said arcuat'e segment being supported on said semi-circular segment by said insulating members, and said insulating members having notches formed therein intermediate said segments, and a yieldable member adapted for engagement with the periphery of said circular disc, and for entering one of said notches to position said disc when said yieldable member comes into engagement with said notch.

2. A circuit controlling device comprising a rotatable shaft, a commutator device rotatably mounted on said shaft, said device comprising a substantially semi-circular segmental plate of conducting material, with an extended central portion for encircling said shaft, an arcuate segment insulatedly mounted on said semi-circular segment, and forming with said semi-circular segment a circular disc, and insulating members extending from said semi-circular segment to said arcuate segment adjacent the periphery of said circular disc, said arcuate segment being supported on said semi-circular segment by said insulating members, and a member adapted for engagement with the periphery of said circular disc.

KENNETH W. JARVIS. 

